Dispenser Control Systems and Methods

ABSTRACT

A method of operating a dispensing system having a material delivery cycle. In some embodiments, the material delivery cycle includes supplying water to a receptacle, performing an operation intended to release a material into the water, and delivering the material to a downstream component. The first step of the method is to initiate the material delivery cycle. Next, a conductivity proximate to the receptacle is monitored. Additionally, one or more error conditions are identified during the material delivery cycle based at least partially on the monitored conductivity.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of and claims priority to U.S. patentapplication Ser. No. 12/524,052, filed Jul. 22, 2009, which is anational stage entry of and claims priority to PCT Application No.PCT/US2008/052672, filed Jan. 31, 2008, which claims priority to U.S.Provisional Application Ser. No. 60/939,142, filed May 21, 2007, andU.S. Provisional Application Ser. No. 60/887,681, filed Feb. 1, 2007,the entire contents of each of which are hereby incorporated byreference.

BACKGROUND

The invention generally relates to material dispensing systems. Morespecifically, the invention relates to methods and systems of operatingand controlling material dispensing systems.

As washing machines (e.g. dish washing machines, clothes washingmachines, etc.) have become more sophisticated, systems have beenimplemented to automatically feed such machines with detergents,sanitizers, rinse aids, and the like, which may be produced in liquid,condensed, compressed, granulated, and/or powdered form. Such materialsmay be automatically delivered to a variety of types of washingmachines.

SUMMARY

In one embodiment, the invention includes a method of operating adispensing system having a material delivery cycle. The materialdelivery cycle includes supplying water to a receptacle, performing anoperation intended to release a material into the water, and deliveringthe material to a downstream component. The method includes initiatingthe material delivery cycle; monitoring a conductivity proximate to thereceptacle; and identifying one or more error conditions during thematerial delivery cycle based at least partially on the monitoredconductivity.

In another embodiment a dispensing system for delivering a material to areceiving component positioned downstream of the dispensing systemincludes a receptacle, a valve, a material metering device, a sensor,and a controller. The valve controls a supply of water to the receptacleand has an off position that prevents water from entering the receptacleand an on position that allows water to enter the receptacle. Thematerial metering device dispenses a material into the receptacle. Thesensor is positioned proximate to the receptacle and generates a firstsignal that is indicative of conductivity. The controller receives thefirst signal from the sensor and generates a valve control signal and amaterial metering device control signal. The valve control signal cantoggle the valve between the on position and the off position. Thematerial metering device control signal can to initiate a dispensing ofthe material. The valve control signal and the material metering devicesignal are generated at least partially in response to a comparison bythe controller of the first signal to one or more stored conductivitythreshold values.

In another embodiment, a method of operating a dispensing systemincludes initiating a material delivery cycle having a pre-flush period,a material dosing period, and a post-flush period. Next, a firstconductivity during the pre-flush period is monitored and compared toone or more thresholds, where the comparison is used to determinewhether to initiate a material delivery during the material dosingperiod. Next, a second conductivity is monitored during the dosingperiod and compared to the one or more thresholds, where the comparisonis used to determine whether material has been dispensed during thematerial dosing period. Next, a third conductivity is monitored during apost-flush period and compared to the one or more thresholds, where thecomparison is used to verify that the material delivered during thedosing period has been delivered to a receiving component positioneddownstream of the dispensing system.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exemplary dispensing system, according to anembodiment of the invention.

FIG. 2 illustrates an exemplary embodiment of a dispensing closure,according to an embodiment of the invention.

FIG. 3 illustrates an exemplary dispensing system, according to anotherembodiment of the invention.

FIG. 4 illustrates an exemplary dispensing system, according to yetanother embodiment of the invention.

FIG. 5 is a block diagram of an exemplary control system, according toan embodiment of the invention.

FIG. 6 illustrates an exemplary process for controlling operations of adispensing system, according to an embodiment of the invention.

FIG. 7-19 illustrate exemplary plots that represent a sensedconductivity during a material delivery cycle, according to anembodiment of the invention.

FIG. 20 illustrates an exemplary embodiment of a condition indicator,according to an embodiment of the invention.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein are for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless specified or limited otherwise, theterms “mounted,” “connected,” “supported,” and “coupled” and variationsthereof are used broadly and encompass both direct and indirectmountings, connections, supports, and couplings. Further, “connected”and “coupled” are not restricted to physical or mechanical connectionsor couplings.

As should also be apparent to one of ordinary skill in the art, thesystems shown in the figures are models of what actual systems might belike. Many of the modules and logical structures described are capableof being implemented in software executed by a microprocessor or asimilar device or of being implemented in hardware using a variety ofcomponents including, for example, application specific integratedcircuits (“ASICs”). Terms like “controller” may include or refer to bothhardware and/or software. Furthermore, throughout the specificationcapitalized terms are used. Such terms are used to conform to commonpractices and to help correlate the description with the codingexamples, equations, and/or drawings. However, no specific meaning isimplied or should be inferred simply due to the use of capitalization.Thus, the claims should not be limited to the specific examples orterminology or to any specific hardware or software implementation orcombination of software or hardware.

FIG. 1 illustrates an exemplary dispensing system 100. Although thisdispensing system will be briefly described below, additional detailsregarding this dispensing system, as well as other dispensing systems,are disclosed in U.S. patent application Ser. No. 11/404,518, filed Apr.14, 2006, which is hereby incorporated by reference.

In some embodiments, the dispensing system 100 is configured to dispenseor deliver a granulated material or powder (e.g., a chemical such as adetergent, a sanitizer, a rinse aid, bleach, pesticides, pool chemicals,etc.). For example, in some embodiments, a granular or powder materialis delivered to a clothes washing machine. In other embodiments, agranular or powder material is delivered to a dish washing machine. Inyet other embodiments, the granular or powder material is delivered todevices or areas, such as a swimming pool, bucket, other wash system,and the like.

In the embodiment shown in FIG. 1, the dispensing system 100 generallyincludes a granulated material or powder container 105 that is supportedin a dispenser assembly or receptacle 110. The container 105 is closedon one end by a metering and dispensing closure 115, which, as describedin greater detail with respect to FIG. 2, can deliver or dose apredetermined amount of material from the container 105 into thereceptacle 110. For example, in one embodiment, the dispensing closure115 is rotated by a drive shaft 120 to deliver the material. The driveshaft 120 is driven by a drive member 125, and is journalled in a collar130 with a seal 135. Other drive systems can be utilized with thissystem, such as those disclosed in U.S. patent application Ser. No.11/404,518.

The dispensing system 100 also includes a water intake conduit 140 thatis controlled by a solenoid valve 145. The water intake conduit 140 andsolenoid valve 145 are utilized to introduce water into the receptacle110. For example, in some embodiments, when the solenoid valve 145 isenergized, water from the water intake conduit 140 is allowed to enterthe receptacle 110. Alternatively, when the solenoid valve 145 isde-energized, water is prevented from entering the receptacle 110. Inother embodiments, a valve mechanism other than the solenoid valve 145may be used.

A water solution outlet conduit 150 is also in communication with thereceptacle 110. For example, the outlet conduit 150 allows water to exitthe receptacle 110. In some embodiments, as described in greater detailbelow, water is mixed with dispensed material prior to exiting thereceptacle 110 through the outlet conduit 150. In the embodiment shownin FIG. 1, liquid or solution is allowed to exit the receptacle 110through the outlet conduit 150 relatively unobstructed. In otherembodiments, the outlet conduit 150 may include a solenoid valve orother valve, similar to the solenoid 145.

In some embodiments, as described in greater detail below, thedispensing system 100 can also include electronic components such as acontroller and one or more conductivity sensors. For example, in oneembodiment, one or more conductivity sensors are positioned in thereceptacle 110 to monitor the conductivity of the receptacle 110 (andthe liquid disposed or flowing therein).

As shown in FIG. 2, the metering and dispensing closure 115 is generallycomposed of three basic components. For example, the closure 115generally includes a cap member 200 with an upstanding wall 205 andinternal threads 210 for engaging complementary threads on the container105. The second component is a rotatable disk 215 with a raisedperipheral wall 220, as well as a cutaway portion 225. Rotatable disk215 is configured to be seated inside the cap member 200. The thirdcomponent is a rotatable disk 230 with a raised peripheral wall 235 anda stub shaft 240 with projections 245. These projections 245 fit throughan opening 250 in the cap member 200 in a manner that the projections245 engage slots 255 in the rotatable disk 215.

Rotatable disks 215 and 230 are rotated by the shaft 120 (see FIG. 1)connected to the stub shaft 240. Additional details regarding theclosure can be found in U.S. Pat. No. 11/404,518, filed Apr. 14, 2006,which is hereby incorporated by reference.

Referring to FIGS. 1 and 2, in operation, the container 105 holding thematerial is supported in the receptacle 110. Water is introduced intothe receptacle 110 through the water intake conduit 140. The meteringand dispensing closure 115 is attached to the container 105. When thedisks 215 and 230 of the closure 115 are properly aligned, the materialfrom the container 105 is free to enter into a measuring opening orchamber 260 as it is uncovered by disk 215 and cutaway 225 (see FIG. 2).However, the material from the container 105 cannot pass into thereceptacle 110, as the passage is blocked by rotatable disk 230.Activation of the drive member 125 and rotation of the drive shaft 120causes the upper rotatable disk 215 and the lower rotatable disk 230 tomove to a second position in which no more material can enter theopening 260, which has become a measuring chamber. Continued rotation ofthe disks 215 and 230 allows for the opening 260 to be positioned overopening 270, which allows the dose of material from the measuringchamber to flow into the receptacle 110 and be mixed with water from theintake conduit 140. The mixed material then exits the receptacle 110through the water solution outlet conduit 150. In some embodiments,multiple doses are delivered during a single delivery cycle.

Referring to FIGS. 3 and 4, additional embodiments of dispensing systemsare shown. In the embodiments shown in FIGS. 3 and 4, components similarto, or the same as, the components shown in FIGS. 1 and 2 are labeledwith like numerals. For example, FIG. 3 illustrates a dispensing system300 that includes two containers 105. In some embodiments, the separatecontainers 105 are utilized to introduce separate powder materials(e.g., a sanitizer and a detergent) to the water supply. FIG. 4illustrates another embodiment of a dispensing system 400 that includesan alternative type of container 105.

The dispensing systems described with respect to FIGS. 1-4 are providedas exemplary systems only. It should be understood that the controlmethods described with respect to FIGS. 5-20 may be applied to a varietyof dispensing systems. For example, in other embodiments, a dispensingsystem need not include a receptacle that contains water. An alternativedispensing system may utilize a separate portion that allows a materialto be dropped into an additional container having a liquid predisposedtherein. Additionally or alternatively, other liquids such as watermiscible and immiscible solvents including water and ether could beemployed in a dispensing system.

Although FIGS. 1-3 illustrate a receptacle that is configured much likea reservoir or holding tank that is selectively filled and emptied, thereceptacle wherein the dispensed chemical and diluent (e.g. water) mixcan have alternative configurations. For example, as illustrated inFIGS. 4A and 4B, the dispenser illustrated in FIG. 4 has a conduit orseries of conduits 111 and 112 defining the receptacle 110.Specifically, the dispensable materials are dispensed from the container105 and into a funnel 111. The dispensable materials are flushed fromthe funnel 111 with water flowing through the funnel 111 from the waterinlet 140. When flushed from the funnel 111, the materials flow throughan angled channel 112 to an outlet 150 of the dispenser 400. As furtherillustrated in these figures, sensors 525 are provided adjacent thewater inlet and channel 112 to sense the condition of the one or moreparameters of the dispenser. Although two sensors are illustrated, moreor less sensors can be utilized in practice. Additional detailsregarding the construction and operation of this type of dispenser isdisclosed in U.S. patent application Ser. No. 11/404,518, filed Apr. 14,2006, which is hereby incorporated by reference.

FIG. 5 is a block diagram of an exemplary control system 500. In someembodiments, the control system 500 can be used, for example, to controlthe components described with respect to the dispensing systems shown inFIGS. 1-4. In other embodiments, the control system 500 may be appliedto an alternative dispensing system. Generally, the control system 500utilizes a controller 505 to operate a solenoid valve 510, a materialmetering device 515, and a dispensing system condition indicator 520.Additionally, the controller 505 receives information from one or moresensors 525, such as conductivity sensors. In some embodiments,additional sensors may be employed, as described in greater detailbelow.

Generally, the controller 505 is a suitable electronic device, such as,for example, a programmable logic controller (“PLC”), a personalcomputer (“PC”), and/or other industrial/personal computing device. Assuch, the controller 505 may include both hardware and softwarecomponents, and is meant to broadly encompass the combination of suchcomponents. In some embodiments, the solenoid valve 510 is a normallyclosed valve that opens when energized. For example, the controller 505transmits a signal to the solenoid valve 510 to open the solenoid valve510. The material metering device 515 can be used to control the amountof material that is dispensed from a container. For example, in someembodiments, the metering device 515 is similar to the closure 115 shownin FIGS. 1-4. Similar to the solenoid valve 510, the metering device 515is controlled via a signal from the controller 505. The conditionindicator 520 can include one or more visual and/or audible indicators(e.g., a light, a liquid crystal display (“LCD”) unit, a horn, etc.) toindicate to a user a condition of the dispensing system (e.g., asdescribed with respect to FIG. 20). In some embodiments, the sensors 525are analog conductivity sensors that transmit a variable signal (e.g., a0-10 volt signal, a 0-10 milliamp signal, etc.) to the controller 505that is indicative of the conductivity of the area surrounding thesensors 525.

In operation, generally, the controller 505 utilizes the informationfrom the sensors 525 to determine how to control the solenoid valve 510,the metering device 515, and the dispensing system condition indicator520. For example, in some embodiments, during a material delivery cycle(e.g., a cycle in which one or more doses of material are dispensed),the controller 505 initially transmits a signal to the solenoid valve510 to energize the solenoid valve 510. Once energized, the solenoidvalve 510 allows water to flow. This initial influx of water can bereferred to as a pre-flush. Additionally, the controller 505 receivesconductivity information via signals from the sensors 525. For example,in some embodiments, when the material is mixed with water, the solutionis substantially more conductive than water alone. Thus, the sensors 525can measure the conductivity of the water and/or water/materialsolution, and generate a corresponding signal that is transmitted to thecontroller 505. The controller 505 utilizes the conductivity informationto determine whether to dispense one or more doses of material into theflowing water. If the controller 505 determines not to dispense thematerial, the controller 505 may generate a dispensing error conditionsignal that is transmitted to the condition indicator 520, which thenindicates the error. After dosing, the controller 505 keeps the solenoidvalve 510 energized to allow the flowing water to clear away thedelivered material. This water flow after dosing can be referred to as apost-flush. Following and/or during the post-flush, the controller 505also utilizes the conductivity information from the sensors 525 toverify that the material was properly administered and/or received bydownstream components. If the controller 505 determines that thematerial was not properly administered and/or received by downstreamcomponents, the controller 505 may generate a dispensing error conditionsignal that is transmitted to the condition indicator 520, which thenindicates the error.

In some embodiments, the control system 500 may include an input devicethat allows a user to input and control one or more user changeablesettings. For example, a user may use the input device to enter amaterial amount (e.g., a number of doses to deliver), a length and/oramount of pre-flush, and a length and/or amount of post-flush. In someembodiments, for example, the pre-flush is adjustable betweenapproximately 1.5 and 5 seconds in duration and the post-flush isadjustable between approximately 2 and 10 seconds in duration.Additionally, as described in greater detail below, a user may enter oneor more conductivity thresholds, which the controller 505 can use todecide whether to deliver the material.

In some embodiments, the control system 500 may contain more componentsthan those shown in FIG. 5. In one embodiment, the control system 500includes multiple sensors for measuring conductivity at differentlocations in a dispensing system. For example, as shown in FIG. 4B, afirst sensor can be positioned near an intake conduit for measuring andverifying water flow, while a second sensor can be positioned in areceptacle near an outlet conduit for measuring the conductivity of awater/material solution. Additionally, a downstream sensor can be addedto the control system 500 that measures the conductivity of thewater/material solution after the solution has exited the receptacle(e.g., in the clothes or dish washing machine). In another embodiment,the control system 500 may include a communication device that allowsthe control system 500 to communicate with other systems. For example,in some embodiments, the control system 500 can track the amount ofmaterial that is available to be dispensed, and transmit a notificationsignal to another system when the material level is low. The controlsystem 500 may also transmit operational information (e.g., dosageamount, length of pre-flush and post-flush, dispensing system errors,etc.) to one or more other systems (e.g., a central control system).Additionally, the control system 500 may be operated by another systemvia the communication system.

In some embodiments, the controller 505 may generate a dispensing errorcondition signal for reasons other than those described above. Forexample, in embodiments that include more than one sensor 525 (e.g., onesensor 525 positioned proximate to a water intake conduit and one sensor525 positioned near an outlet conduit), the controller 505 may generatea dispensing error condition signal if the signals from the sensors 525are not consistent. For example, if the sensor that is proximate to thewater intake conduit 525 indicates that water is present, but the sensor525 that is proximate to the outlet conduit does not indicate that wateris present, a dispensing error condition may be identified. In anotherembodiment, an error condition signal may be generated if a problem withthe communication system is identified (e.g., the communication systemis unable to transmit information to other systems).

FIG. 6 illustrates a process 600 for controlling the operations of adispensing system (e.g., the dispensing system 100) using a controlsystem (e.g., the control system 500) during a material delivery cycle.In some embodiments, the process 600 can also be used to verify that amaterial has been properly delivered, as well as provide an indicationof how much material has been delivered. While the process 600 isdescribed as being carried out by the components included in thedispensing system 100 and/or the control system 500, in otherembodiments, the process 600 can be applied to other systems.

The first step in the process 600 is to begin measuring conductivity inthe receptacle 110 (step 605). This can be accomplished, for example, byinitializing the conductivity sensor 525. In some embodiments, theconductivity sensor 525 is in constant operation, generating andtransmitting signals indicative of conductivity to the controller 505,and does not need to be initialized. Next, water is supplied to thereceptacle 110 for a pre-flush operation (step 610), and a change inconductivity is verified (step 615). For example, the controller 505verifies that the conductivity monitored by the sensor 525 changes whenwater is added. The controller 505 can verify or determine ifconductivity changes are appropriate by comparing the conductivitysignal from the sensor 525 to a stored set of conductivity thresholds.With reference to FIG. 6, the conductivity comparisons are described ingeneral terms (e.g., a change in conductivity). However, severalspecific exemplary plots of conductivity over time are provided withrespect to FIGS. 7-19. These plots provide specific examples in whichconductivity values are compared with one or more conductivitythresholds to identify whether conductivity values are appropriate.

The comparison of conductivity values to conductivity thresholds canalso aid in determining whether a dispensing error condition is present.For example, if the conductivity that is monitored by the sensor 525does not change in accordance with bounds or thresholds set in thecontroller 505 pertaining to a material delivery cycle, a dispensingerror condition may be indicated (e.g., displayed by the conditionindicator 520) (step 620). For example, in some embodiments, thecondition indicator 520 can indicate a dispensing error condition usingan array of lights (e.g., as described with respect to FIG. 20). Inanother embodiment, as previously described, the condition indicator 520can indicate a dispensing error condition using an LCD unit, or similarvisual device. Additionally or alternatively, an audible alarm may beused to indicate a dispensing error condition, or a message may be sent.As described in greater detail below, dispensing error conditions mayinclude a “no water” condition, a “blocked dispenser” or a “blocked flowpath” condition, and/or an “out of product” condition. Other dispensingerror conditions are also possible (e.g., a “drive failure” condition, a“solenoid valve failure” condition, etc.). Furthermore, some conditionscan be further refined, such as the “blocked flow path” condition, toindicate whether the condition is caused upstream or downstream from thesensor.

Referring still to FIG. 6, if the conductivity monitored by the sensor525 changes in accordance with the limits or thresholds set in thecontroller 505, the controller 505 then determines whether to dispenseone or more doses of material (step 625). If the controller 505determines not to dispense the material, a dispensing error conditionmay be indicated (step 630). Such a determination may be made, forexample, if there is a change in conductivity monitored by the sensor525, but the change is not consistent with certain conductivitythresholds. If the controller 505 determines to dispense one or moredoses of material, such doses are dispensed and the conductivity ismeasured while dosing (step 632). The next step in the process 600 is todetermine if the conductivity monitored by the sensor 525 changesappropriately during and/or after dosing (step 635). If the change inconductivity is not appropriate, or there is no change in conductivityat all, a dispensing error condition may be indicated (step 637). If theconductivity change is appropriate, delivery of the material iscompleted and a post-flush operation is initiated (step 640), and afinal conductivity change is verified (step 645). If the final change inconductivity is not appropriate, or there is no change in conductivityat all, a dispensing error condition may be indicated (step 650). If thechange in conductivity is appropriate, the process 600 ends (step 655),and the material delivery cycle is complete. Upon completion, thecontroller 505 can determine or verify that the material has beenproperly delivered. The controller 505 can also determine how muchmaterial was delivered by determining how many doses were delivered(e.g., see step 632). The process 600 is completed each time a materialdelivery cycle is initiated.

In other embodiments, an alternative process may be used to deliver thematerial to the receptacle 110. For example, in some embodiments,conductivity may be verified at additional points during the process.Additionally or alternatively, other parameters may be monitored (e.g.,material weight, inductance, turbidity, etc.) and used to determine ifone or more doses of material should be delivered and/or if the doseswere properly received.

FIGS. 7-19 illustrate exemplary plots of conductivity over time. Theplots contain conductivity traces that can be used, for example, todetermine a condition of a dispensing system (such as the dispensingsystem 100) during a material delivery cycle. For example, in oneembodiment, the controller 505 can generate conductivity traces similarto those shown in the plots using signals from the sensor 525. Thecontroller 505 can then compare the conductivity values monitored by thesensor 525 to conductivity thresholds in order to determine a conditionof the dispenser system 100 and optionally take further action (e.g.,alert a user and/or send signals to modify operation of the dispensingsystem). As should be recognized by one of ordinary skill in the art,the plots in FIGS. 7-19 set forth only several examples of possibleconductivity values during a material delivery cycle, and the controller505 is capable of determining a condition of the dispensing system 100based on a variety of conductivity values. Generally, as described ingreater detail below, in addition to absolute conductivity (e.g., themagnitude of the conductivity signal from the sensor 525), conductivitytransitions (e.g., changes in conductivity) can be used to determine acondition of the dispensing system 100.

FIG. 7 illustrates an exemplary plot 700 that represents an idealreceptacle conductivity (as monitored by the sensor 525) during amaterial delivery cycle when relatively “soft” water is supplied to thereceptacle 110 via the intake conduit 140. For example, during an idleperiod 705, the conductivity of the receptacle 110 is relatively low.This is due to the receptacle 110 being relatively empty or dry and thesolenoid 145 being in an “off” position, which prevents water fromentering the receptacle 110. During a pre-flush period 710, the solenoidis activated, allowing water into the receptacle 110. As such, theconductivity rises from the idle level, representing the conductivity ofthe soft water supply. During a dosing or dispensing period 715, thedrive 125 is activated, which causes the closure 115 to deliver one ormore doses of material from the container 105 into the receptacle 110.As such, the conductivity again rises, representing the conductivity ofthe water/material solution in the receptacle. A dip or depression 720may be present during the dosing period 715 due to the rotation of theclosure 115 and the interruption of material entering the water. Afterthe delivery of the material has been completed, the solenoid 145remains activated and water continues to flow through the receptacle.This post-delivery period can be referred to as a post-flush period 725.During the post-flush period 725, the conductivity quickly falls to thelevel of the pre-flush period 710 as the material is taken away andwater remains. After the post-flush period 725 is completed, thesolenoid valve 145 is deactivated (i.e., the water supply is shut off),and the conductivity level falls. During a second idle period 730 thereceptacle 110 is once again relatively empty and dry.

FIG. 8 illustrates an exemplary plot 800 that represents an idealreceptacle conductivity during a material delivery cycle when relatively“hard” water is supplied to the receptacle 110 via the intake conduit140. In some aspects, the plot 800 is similar to the plot 700. Forexample, the plot 800 includes an idle period 805, a pre-flush period810, a dosing period 815, a post-flush period 825, and a second idleperiod 830 during which a chain of events similar to those describedwith respect to FIG. 7 occurs. However, due to differences in mineralconstituents of the water, the conductivity levels during the periods810-825 may be different. For example, as shown in FIG. 8, the pre-flushperiod 810 and post-flush period 825 exhibit slightly higherconductivities than those shown in FIG. 7.

FIG. 9 illustrates an exemplary plot 900 that represents an idealreceptacle conductivity during a material delivery cycle, similar tothat shown in FIG. 7. However, in the embodiment shown in FIG. 9,material dosing has been interrupted or paused during delivery. Forexample, the conductivity begins at a level consistent with a dosingperiod 905, and then falls to a level consistent with a post-flushperiod 910 and an idle period 915. The conductivity then rises to alevel consistent with a pre-flush period 920 and another dosing period925. In some embodiments, such pausing and resuming can be implementedduring a system calibration. For example, in some embodiments, thedispensing system 100 includes a calibration mode that allows for atleast a portion of the water and/or water/material solution to be testedwith the sensor 525 (or another sensor) prior to being released from thedispensing system 100. During the calibration mode, a calibrationchamber may be used to collect the water and/or water/material solution.In order to ensure that the calibration chamber does not overflow, thedosing of material can be paused, allowing the calibration chamber toempty. The dosing can then be resumed once the calibration system hasreached equilibrium.

In some embodiments, the pause and resume functions may be useddifferently. For example, in some embodiments, solution concentration(i.e., the amount of dispensed material per unit of water) is measureddownstream from the dispensing system 100 (e.g., in an associatedwashing machine). If the solution concentration approaches or reaches amaterial concentration set point (e.g., a concentration set point storedin the controller 505), the dispensing system 100 can be paused whilethe number of material doses actually delivered is verified. Thedispensing system 100 can then be recalibrated accordingly. For example,the system 100 can recalculate the number of doses of material needed toincrease the washing machine tank's conductivity by a predeterminedamount. Other recalibration schemes are also possible.

In another embodiment, the pause and resume functions may be used whiledelivering two materials to the receptacle 110 (see FIG. 3). Forexample, in some embodiments, 0-240 doses of a first material are fedfor every dose of another material. Due to power and/or drive componentconstraints, only one material may be fed at a time. Thus, delivery ofthe one material may be paused while delivery of the other material iscompleted.

In yet another embodiment, the pause and resume functions may be used indispensing systems that do not include a conductivity sensor (or whenthe conductivity sensor is turned off). In such embodiments, anassociated downstream washing machine may send a trigger signal to thedispensing system as a request to deliver the material. If the triggersignal is lost or interrupted during delivery, the material dosing maybe paused until the trigger signal is restored.

FIG. 10 illustrates an exemplary plot 1000 that represents an idealreceptacle conductivity during a material delivery cycle with multipleconductivity thresholds applied. Similar to the plot 700 shown in FIG.7, the plot 1000 includes an idle period 1005, a pre-flush period 1010,a dosing period 1015, a post-flush period 1020, and a second idle period1025. However, the plot 1000 also includes a water conductivitythreshold 1030 (e.g., water conductivity relative to the sum of dryconductivity and an offset), a maximum dry conductivity limit 1035, achemical conductivity threshold 1040 (e.g., chemical conductivityrelative to the sum of water conductivity and an offset), and a maximumwater conductivity limit 1045.

The water conductivity threshold 1030 is set relative to dryconductivity (e.g., the conductivity of the idle period 1005).Generally, the water conductivity threshold 1030 is set just above thedry conductivity (e.g., an offset from the dry conductivity) to providea differentiation between a dry receptacle 110 and a receptacle 110 thatincludes water. For example, the controller 505 can determine that thereceptacle 110 contains water if the signal from the sensor 525 breachesthe water conductivity threshold 1030. In some embodiments, the waterconductivity threshold 1030 is variable, and allows for a user tospecify a tolerance range for the sensor 525 to provide accuratedetection of the presence or absence of water despite variations in thedry conductivity. For example, for a relatively wide tolerance, the usermay choose to set the water conductivity threshold 1030 a relativelygreater amount above the dry conductivity. Setting a relatively widetolerance can allow the controller 505 to determine that the receptacle110 is substantially empty and dry, even if a small amount of waterand/or material is present.

The maximum dry conductivity limit 1035 is set to ensure that the dryconductivity monitored by the sensor 525 is valid. For example, the dryconductivity of the receptacle 110 should be below the maximum dryconductivity limit 1035 for the controller 505 to determine that the dryconductivity value is valid. Generally, the maximum dry conductivitylimit 1035 is a fixed limit.

The chemical conductivity threshold 1040 is set relative to the waterconductivity (e.g., relative to the conductivity monitored during thepre-flush period 1010 or the post-flush period 1020). Generally, thechemical conductivity threshold 1040 is set at a point above the waterconductivity (e.g., an offset from the water conductivity), whichprovides a differentiation between a receptacle 110 that contains onlywater and a receptacle 110 that contains water and the material (e.g., achemical). For example, the controller 505 can determine that the waterin the receptacle 110 contains the material if the conductivity signalfrom the sensor 505 breaches the chemical conductivity threshold 1040(provided that the solution containing water and the material has ahigher conductivity than water alone). In some embodiments, the chemicalconductivity threshold 1040 is variable, and is set relative to thewater conductivity to allow the controller 505 to accurately detect thepresence or absence of material despite relatively wide variations inwater conductivity. The chemical conductivity threshold 1040 also allowsa user to specify a tolerance range for the sensor 525. For example, fora relatively wide tolerance, the user may choose to set the chemicalconductivity threshold 1040 a relatively greater amount above the waterconductivity. Setting a relatively wide tolerance can allow thecontroller 505 to determine that the receptacle 110 contains only water,even if a small amount of material is present.

The maximum water conductivity limit 1045 is set to ensure that thewater conductivity monitored by the sensor 525 is valid. For example,the water conductivity of the receptacle 110 should be below the maximumwater conductivity limit 1045 for the controller 505 to determine thatthe water conductivity value is valid. Generally, the maximum waterconductivity limit 1045 is a fixed limit.

In other embodiments, more or fewer conductivity thresholds may be set.For example, in one embodiment, the absolute conductivity thresholds arenot employed, leaving only the water conductivity threshold 1030 and thechemical conductivity threshold 1040. Alternatively, more conductivitythresholds may be implemented, for example, a maximum chemicalconductivity threshold.

FIG. 11 illustrates an exemplary plot 1100 that represents a materialdelivery cycle in which material residue has adhered to the sensor 525and has dried. For example, as shown in FIG. 11, the conductivity duringa first idle period 1105 is slightly higher than that of an idealconductivity trace 1110. However, since the conductivity is still belowa maximum dry conductivity limit 1115 (e.g., the conductivity of theresidue is not great enough to breach the maximum dry conductivity limit1115), the operation of the dispensing system is unaltered. Accordingly,the conductivity through a pre-flush period 1120, a dosing period 1125,a post-flush period 1135 and a second idle period 1140 is similar to theideal conductivity shown in FIG. 7. Accordingly, a dispensing errorcondition is not identified because the conductivity remains within thethresholds throughout the material dispensing cycle. In someembodiments, the water during the post-flush period 1135 is sufficientto clear the residue from the sensor 525. As such, the conductivityduring the second idle period 1140 may be lower than the conductivityduring the first idle period 1105.

FIG. 12 illustrates an exemplary plot 1200 that represents a materialdelivery cycle in which material residue has adhered to the sensor 525and is still wet. For example, as shown in FIG. 12, the conductivityduring an idle period 1205 exceeds an absolute or maximum waterconductivity limit 1210 (in addition to a maximum dry conductivity limit1215 and a chemical conductivity threshold 1220). During a pre-flushperiod 1225, the water clears the sensor 525 of the material residue,and the conductivity begins to fall. After the conductivity has fallenbelow the maximum water conductivity limit 1210, a dosing period 1230begins and material is delivered. If the conductivity does not fallbelow the maximum water conductivity limit 1210, as described in greaterdetail with respect to FIG. 16, material may not be delivered during thedosing period 1230. Following the dosing period 1230, the water from thepost-flush period 1235 clears material residue from the sensor 525,thereby allowing the conductivity to fall. In some embodiments, adispensing error condition may be initially identified due to theelevated conductivity during the idle period 1205. This dispensing errorcondition can be indicated using one or more visual and/or audiblesignals (e.g., a color-coded light of the condition indicator 520).However, as described above, material delivery is still allowed to occurdue to the change in conductivity during the pre-flush period 1225. Insome embodiments, each error condition that is identified during amaterial dispensing cycle is also registered or stored in the controller505 (or another accessible memory location), such that a user can accessthe stored error conditions. In this way, the user may be able to moreeasily identify past errors, and use that knowledge to repair ortroubleshoot the dispensing system.

FIG. 13 illustrates an exemplary plot 1300 that represents a materialdelivery cycle in which the sensor 525 has been disconnected, or thereceptacle 110 has been blocked upstream of the sensor 525. For example,as shown in FIG. 13, conductivity trace 1305 is relatively flat and lessthan conductivity thresholds 1310. As a result, a dispensing errorcondition is identified, and can be indicated using one or more visualand/or audible signals. In some embodiments, as described with respectto FIG. 20, each identified dispensing error condition is indicatedusing a distinct visual and/or audible signal, which allows a user todifferentiate between error conditions. For example, in the embodimentshown in FIG. 13, a “no water” dispensing error condition is identifiedand displayed by the condition indicator 520 (e.g., a colored light thatcorresponds to the “no water” error condition is lit). Accordingly, auser can quickly identify that the sensor 525 is either disconnected andunable to sense conductivity, or that water is not being supplied. Asdescribed above, an error condition flag may also be set in thecontroller 505. In other embodiments, once a dispensing error conditionis identified, the controller 505 may transmit signal(s) to modifyoperation (e.g., deactivate component(s) of the dispensing system).

FIG. 14 illustrates an exemplary plot 1400 that represents a materialdelivery cycle in which the water supply fails during material delivery.For example, the conductivity during an idle period 1405 and a pre-flushperiod 1410 approximately follows that of an ideal conductivity trace1415. However, after a dosing period 1420, the conductivity does notfall in accordance with the ideal conductivity trace 1415. This isbecause the water supply has been removed, allowing the material thatwas delivered during the dosing period 1420 to remain in the receptacle110 and in contact with the sensor 525. In the embodiment shown in FIG.14, a “blocked flow path” or “block dispenser” dispensing errorcondition is identified and displayed by the condition indicator 520. Insome embodiments, additional dosing will not be performed after thiserror condition is identified. For example, a user may have to manuallyclear the blockage and/or acknowledge the error (e.g., by clearing theerror flag in the controller) prior to the dispensing system resumingoperation.

FIG. 15 illustrates an exemplary plot 1500 that represents a materialdelivery cycle in which a slurry that includes the dispensed materialand water has adhered and dried to a probe of the sensor 525. Forexample, during an idle period 1505, the conductivity is generally lowerthan a maximum dry conductivity limit 1510, indicating that thereceptacle 110 is generally free of water and material. However, duringa pre-flush period 1515, the conductivity rises above an absolute ormaximum water conductivity limit 1520 due to rewetting of dried materialon the sensor 525. Additionally, in the embodiment shown in FIG. 15, theconductivity does not fall below the maximum water conductivity limit1520 until after a dosing period 1525 has begun. As a result, a “blockeddispenser” dispensing error condition is identified, and indicated bythe condition indicator 520. In some embodiments, upon identifying a“blocked dispenser” error condition, the controller 505 preventsmaterial delivery. As such, the conductivity continues to fallrelatively slowly. In some embodiments, the water continues to flow evenif the material is not delivered. This water flow can contribute to thedeclining conductivity, as some of the slurry is removed from the areanear the sensor 525. As described with respect to FIG. 14, a user mayhave to manually clear the slurry and/or acknowledge the error prior tothe dispensing system resuming operation.

FIG. 16 illustrates an exemplary plot 1600 that represents a materialdelivery cycle in which a water supply is unavailable and a slurry hasadhered to a probe of the sensor 525. For example, during an idle period1605, the conductivity is greater than an absolute or maximum waterconductivity limit 1610 due to the slurry on the sensor 525. As aresult, an error condition may be identified. However, as described withrespect to FIG. 12, rather than halt operation, controller 505 attemptsto clear the sensor 525 by releasing water during a pre-flush period. Inthe embodiment shown in FIG. 16, the water supply is unavailable (e.g.,water is not being supplied to the intake conduit 140, the solenoidvalve 145 has failed, etc.), and, accordingly, the conductivity levelremains above the maximum water conductivity limit 1610. As a result, a“blocked dispenser” error condition is identified and indicated by thecondition indicator 520. Additionally, the controller 505 prevents amaterial delivery or dosing from occurring. Again, a user may have tomanually clear the slurry and/or resolve the water supply problem beforecontinued operation can occur. Alternatively, if a plurality of sensorsare used (such as illustrated in FIG. 4B), a sensor can be used to sensewater flow at the inlet and help isolate the problem either as a “nowater” condition or a “blocked dispenser/flow path” condition.

FIG. 17 illustrates an exemplary plot 1700 that represents a materialdelivery cycle in which the material to be dispensed is unavailable(e.g., the supply of material is exhausted). For example, as shown inFIG. 17, during an idle period 1705, the conductivity is below a waterconductivity threshold 1710. During a pre-flush period 1715, theconductivity rises to a level consistent with the conductivity of thesupply water (e.g., the water from the intake conduit 140). However,during a dosing period 1720, rather than an increase in conductivitysimilar to that of an ideal conductivity trace 1725, the conductivityremains at approximately the level of the pre-flush period 1715 (theconductivity does not rise above a chemical conductivity threshold1730). As a result, an “out of product” dispensing error condition isidentified and indicated by the condition indicator 520. In someembodiments, the controller 505 may attempt to continue with materialdelivery (e.g., by rotating the closure 115 to dispense a dose) in orderto automatically prime the dispensing system 100 for the next materialdelivery. However, if the “out of product” dispensing error condition isidentified during subsequent material delivery cycles, the controller505 may halt operation, and require a user to manually refill thecontainer 105 with material or replace the container 105.

FIG. 18 illustrates an exemplary plot 1800 that represents a materialdelivery cycle in which the supply of material has been exhausted in themiddle of a powder delivery. As shown in FIG. 18, the conductivityfollows that of an ideal conductivity trace 1805 throughout half of thematerial delivery cycle, but rapidly falls during a dosing period 1810as the material runs out. As such, the conductivity falls below achemical conductivity threshold 1815 during the dosing period 1810, andan “out of product” dispensing condition error is identified andindicated by the condition indicator 520. Similar to the embodimentshown in FIG. 17, the controller 505 may attempt to continue withmaterial delivery (e.g., by rotating the closure 115 to dispense anotherdose) in order to automatically prime the delivery system 100 for thenext material delivery. However, if the “out of product” dispensingerror condition is identified during subsequent material deliverycycles, the controller 505 may halt operation, and require a user tomanually refill the container 105 with material.

FIG. 19 illustrates an exemplary plot 1900 that represents a materialdelivery cycle in which the portion of the receptacle 110 leading to theoutlet conduit 150 has been blocked with material, but water is stillable to seep through the blockage. For example, during an idle period1905, the conductivity is below a water conductivity threshold 1910.However, during a pre-flush period, the conductivity rises to a pointabove a maximum water conductivity limit 1915. As a result, a “blockeddispenser” dispensing error condition is identified and indicated by thecondition indicator 520. Due to the “blocked dispenser” dispensing errorcondition, no material delivery is attempted, but the water continues tobe supplied. Accordingly, the conductivity remains approximatelyconstant throughout a dosing period 1920 and a post-flush period 1925.After the water supply has been removed, the conductivity falls, butremains above the maximum water conductivity limit 1915. A user may haveto manually clear the blockage and/or acknowledge the error prior to thedispensing system resuming operation. In some embodiments, however, thematerial delivery cycle will be repeated in an attempt to clear theblockage. In such embodiments, water may be supplied during thepre-flush period for a certain number of material delivery cycles (e.g.,three delivery cycles). To avoid an overflow condition, however, in someembodiments, water will no longer be supplied during the pre-flushperiod after three failed material delivery cycles. As such, a user mayhave to manually clear the blockage and/or acknowledge the error priorto the dispensing system resuming operation.

FIG. 20 illustrates an exemplary embodiment of a condition indicator2000 for a dispensing system, such as the dispensing system 100, thatincludes three materials (e.g., a detergent material, a sanitizermaterial, and a rinse aid material). In other embodiment, the conditionindicator 2000 may be adapted to a system that includes more or fewermaterials than those shown in FIG. 20. The condition indicator 2000generally includes a detergent material indicator light element 2005, asanitizer material indicator light element 2010, and a rinse aidmaterial indicator light element 2015 that correspond to the threematerials. Additionally, in some embodiments, the condition indicator2000 includes a message display (e.g., an LCD or similar type ofdisplay). In other embodiments, the condition indicator 2000 can includemore or fewer lights (or other indicating components) than those shownin FIG. 20. For example, in some embodiments, the condition indicatormay include additional light elements (e.g., a plurality of differentcolored light elements). Alternatively, the condition indicator mayinclude fewer light elements (e.g., a single light element that changescolor).

Generally, the light elements 2005-2015 can be used to indicate acondition of the dispensing system and/or a status of each material. Forexample, in one embodiment, as described in greater detail below, thelight elements 2005-2015 change color according to the condition of thedispensing system. For example, a green light can indicate that thedispensing system is operating properly. However, if an error conditionis identified, the light may change color to indicate to a user that anerror condition is present.

For example, in one embodiment, after an error condition has beenidentified (e.g., a “blocked receptacle” condition), a yellow flashinglight is used to indicate that the material dispensing system has beendisabled (i.e., material will not be dispensed during a dosing period).In order to clear the error condition and continue with dispensingsystem operation, power to the dispensing system 100 may have to beremoved and then restored. In other embodiments, the error condition maybe cleared using another method, for example, with an input devicelocated on the face of the condition indicator (e.g., a “clear fault”pushbutton).

In some embodiments, the dispensing system is not disabled until after acertain number of errors or faults have been identified, or after apredetermined time period has elapsed. For example, a controller canregister and/or store identified error conditions as they areidentified, and disable the dispensing system after three consecutiveerror conditions. Such embodiments can minimize disabling of thedispensing system due to faulty identified error conditions.

Various features of the invention are set forth in the following claims.

1. A method of operating a dispensing system adapted to dispensematerial from a container, the method comprising: connecting thecontainer to a receptacle at least partially contained within thedispensing system; supplying water to the receptacle; performing anoperation intended to release material into the water from thecontainer; monitoring a conductivity proximate the receptacle via asensor positioned to sense conductivity in the receptacle; deliveringthe material and water from the receptacle through an outlet conduit ofthe dispensing system for use in cleaning operations by a downstreamcomponent; identifying one or more error conditions via a controllerduring at least one of the steps of supplying water to the receptacle,performing an operation intended to release material into the water, anddelivering the material and water; and determining a location within thedispensing system where the one or more error conditions has occurredbased on the identification of the one or more error conditions.
 2. Themethod of claim 1, further comprising: supporting the container in thereceptacle; and delivering the material to a washing machine that ispositioned downstream of the dispensing system.
 3. The method of claim1, wherein performing an operation intended to release material into thewater comprises releasing a powder material or a granulated materialinto the water.
 4. The method of claim 1, wherein performing anoperation intended to release material into the water comprisesoperating a material metering device to release one or more doses ofmaterial into the water.
 5. The method of claim 1, wherein identifyingthe one or more error conditions includes comparing the monitoredconductivity to one or more stored thresholds.
 6. The method of claim 5,wherein comparing the monitored conductivity to one or more storedthresholds includes comparing the conductivity to a first threshold anda second threshold, the first threshold corresponding to the sum of aconductivity of the receptacle when the receptacle is relatively dry anda first offset value, the second threshold corresponding to the sum of aconductivity of the receptacle when the receptacle includes water and asecond offset value.
 7. The method of claim 6, further comprisingidentifying a blocked receptacle error condition via the controllerduring at least one of the steps of supplying water to the receptacle,performing an operation intended to release material into the water, anddelivering the material and water in response to the monitoredconductivity being greater than the second threshold.
 8. The method ofclaim 6, further comprising identifying a blocked receptacle errorcondition via the controller prior to the operation intended to releasethe material in response to the monitored conductivity being greaterthan the second threshold.
 9. The method of claim 6, further comprisingidentifying a no water error condition via the controller during atleast one of the steps of supplying water to the receptacle, performingan operation intended to release material into the water, and deliveringthe material and water in response to the monitored conductivity beingnot greater than the first conductivity.
 10. The method of claim 6,further comprising identifying an out of material condition via thecontroller while the operation intended to release the material is beingperformed during at least one of the steps of supplying water to thereceptacle, performing an operation intended to release material intothe water, and delivering the material and water in response to themonitored conductivity being not greater than the second threshold. 11.The method of claim 1, further comprising identifying a low water flowerror condition associated with supply of water in response to themonitored conductivity being lower than a predetermined conductivitythreshold.
 12. A method of operating a dispensing system adapted todispense material from a container, the method comprising: connectingthe container to a receptacle at least partially contained within thedispensing system; supplying water to the receptacle; performing anoperation intended to release material into the water from thecontainer; delivering the material and water from the receptacle throughan outlet conduit of the dispensing system for use in cleaningoperations by a downstream component; monitoring a first conditionwithin the dispensing system via a first sensor positioned within thedispensing system, the first sensor configured to generate a firstsignal indicative of the first condition; monitoring a second conditionwithin the dispensing system via a second sensor positioned within thedispensing system upstream of the first sensor, the second sensorconfigured to generate a second signal indicative of the secondcondition; identifying one or more error conditions via a controllerbased on the first signal and the second signal during at least one ofthe steps of supplying water to the receptacle, performing an operationintended to release material into the water, and delivering the materialand water.
 13. The method of claim 12, further comprising identifyingthe one or more error conditions when the first and second signals areinconsistent with each other.
 14. The method of claim 12, furthercomprising identifying a blocked container error condition in responseto the first signal indicative of a conductivity within the receptaclebelow a predetermined threshold and the second signal indicative ofwater being supplied to the receptacle.
 15. The method of claim 12,further comprising identifying a blocked water supply error condition inresponse to the first signal indicative of a conductivity within thereceptacle above a first predetermined threshold and the second signalindicative of a conductivity at or below a second predeterminedthreshold.
 16. The method of claim 12, further comprising identifying ablocked receptacle error condition prior to the operation intended torelease the material in response to the first signal indicative of aconductivity within the receptacle being greater than a predeterminedconductivity threshold and the second signal indicative of water beingsupplied to the receptacle.
 17. A dispensing system adapted to dispensematerial from a container, the dispensing system comprising: areceptacle positioned in communication with the container to receivematerial from the container via a dispenser; a water supply positionedto supply water to the receptacle; an outlet conduit fluidly coupled tothe receptacle to deliver material and water from the receptacle to adownstream component; a first sensor positioned within the dispensingsystem and configured to monitor a first condition within the dispensingsystem, the first sensor configured to generate a first signalindicative of the first condition; a second sensor positioned within thedispensing system upstream of the first sensor and configured to monitora second condition within the dispensing system, the second sensorconfigured to generate a second signal indicative of the secondcondition; a controller programmed to identify one or more errorconditions based on the first signal and the second signal during atleast one of the steps of supplying water to the receptacle, performingan operation intended to release material into the water, and deliveringthe material and water.
 18. The dispensing system of claim 17, whereinthe controller is programmed to identify the one or more errorconditions in response to the first and second signals beinginconsistent with each other.
 19. The dispensing system of claim 17,wherein the one or more identified error conditions includes a blockedcontainer error condition in response to the first signal indicative ofa conductivity within the receptacle below a predetermined threshold andthe second signal indicative of water being supplied to the receptacle.20. The dispensing system of claim 17, wherein the one or moreidentified error conditions includes a blocked receptacle errorcondition prior to the operation intended to release the material inresponse to the first signal indicative of a conductivity within thereceptacle being greater than a predetermined conductivity threshold andthe second signal indicative of water being supplied to the receptacle.